1. Field of the Invention
This invention relates generally to pendulous linear accelerometers and more particularly to the dual use of flexure pivots to serve the purposes of bearings for supporting the sensitive pendulous mass and also as the calibrated force spring for the system of the accelerometer.
2. Description of the Prior Art
Accelerometers are known in which a pendulous mass is mounted in a support such that a movement of the support coupled with the inertia of the mass causes a relative displacement between the pendulous mass and the support. An output signal may be derived from this relative displacement so as to relate to the force, and thus the acceleration, causing the initial movement. The simple accelerometer thus portrayed is beset with many difficulties among which reliable and maintained calibration is one of the most important and troublesome. For example, subsequent to the experience of an acceleration causing the relative displacement mentioned between the pendulous mass and the support, how can the prior spatial relationship be restored? If this problem is not solved, it is difficult to determine the value of the acceleration involved since the "at-rest" positions of the elements of the accelerometer are not known with any degree of certainty. It is also necessary to eliminate the effects of accelerations and disturbing vibrations incident at cross-axes.
There is, therefore, a continuing requirement in the art for improved pendulous accelerometers that provide some alleviation in respect to the shortcomings mentioned above, among others.
It would thus be a great advantage to the art to provide a reliable pendulous linear accelerometer that is easy to calibrate and that will hold that calibration for a relatively long period of time.
Another great advantage to the art would be the provision of such a reliable accelerometer in an economical package.
A further desirable advantage to the art would be the provision of such an accelerometer exhibiting, in addition to its other advantages, a high degree of cross-axis rigidity.